Eduardo Galeano is an amazing writer who was actually on the list of people Argentina wanted to assassinate when he was living there, and he had to leave the area during its US-backed "Dirty War," during which it's estimated 30,000 suspected "leftists" were tortured, murdered, "disappeared."
The pregnant mothers who were kidnapped and tortured were occasionally given Caesarian operations when they were near their delivery dates, and those infants taken were given out to politically popular military figures, or politicians, etc., and the mothers, as well as the fathers were taken to airplanes and thrown out, bound by chains to other prisoners, into the ocean, or large rivers in the country.
Mr. Galeano has written many books but his "Open Veins" is well read throughout the world.
Otherwise, there are so many books it's hard to pick one other overall book. There are books concerning conditions, histories, situations in every country, dictators, military juntas, etc., etc. I have so many I still have books I haven't had time to read them through, yet. Once you start looking for information you will find enough to keep you busy almost forever, it seems.
A good website is Green Left Weekly, or https://zcomm.org/znet/ or http://upsidedownworld.org/main/home-mainmenu-1 or Colombia Reports, which is the only English-speaking news source in Colombia.
There are many others but these could give you a basic beginning.
You are very young. Your very best bet would be to try to get in as much basic history of the Americas you can, in shortened form, and if you are interested in the role the U.S. has played in the Americas, the really intensive, heavy stuff close enough in time to us to have any media coverage, started in 1954 in Guatemala, when U.S. President Dwight D. Eisenhower had his Marines overthrow the Guatemalan government of leftist President Jacobo Arbenz, on behalf of the United Fruit Company (known as Chiquita Banana in the present) upon whose board sat the brother of Eisenhower's Secretary of State, John Foster Dulles. That brother also became the head of the U.S. CIA. United Fruit had taken vast areas of land in Guatemala, owned the railroad, and worked the citizens at very near slave wages. They didn't like Arbenz' plans to redistribute land to help the desperately poor people of that country.
This pattern has been repeated relentlessly since that time, in various manifestations. Truly sad.
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